Attachment 11839 Details for Bug 11714 – Patch for 4.2, 4.3 and 4.4 cherry-picked from master

[patch] Patch for 4.2, 4.3 and 4.4 cherry-picked from master

v42,v43,v44-addrchange.patch (text/plain), 3.56 KB, created by Ralph Böhme on 2016-02-15 12:31:10 UTC

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Creator: Ralph Böhme

Created: 2016-02-15 12:31:10 UTC

Size: 3.56 KB

patch

obsolete

>From 4f8fbc132bc82f61a5bf8a478245db8c2bd3471a Mon Sep 17 00:00:00 2001
>From: Ralph Boehme <slow@samba.org>
>Date: Thu, 4 Feb 2016 15:35:06 +0100
>Subject: [PATCH] lib/tsocket: workaround sockets not supporting FIONREAD
>MIME-Version: 1.0
>Content-Type: text/plain; charset=UTF-8
>Content-Transfer-Encoding: 8bit
>
>Netlink sockets don't support querying pending bytes with ioctl(fd,
>FIONREAD, ...) and would return EOPNOTSUPP, so use recvmsg() with
>MSG_PEEK|MSG_TRUNC as a fallback.
>
>The MSG_TRUNC flag to recvmsg() is Linux only, but netlink is as well,
>so we're safe for now.
>
>Bug: https://bugzilla.samba.org/show_bug.cgi?id=11714
>
>Signed-off-by: Ralph Boehme <slow@samba.org>
>Reviewed-by: Amitay Isaacs <amitay@gmail.com>
>Reviewed-by: Martin Schwenke <martin@meltin.net>
>
>Autobuild-User(master): Ralph BÃ¶hme <slow@samba.org>
>Autobuild-Date(master): Wed Feb 10 10:30:24 CET 2016 on sn-devel-144
>
>(cherry picked from commit 574313a1e11d521ba3f7232ff0b4186b49658199)
>---
> lib/tsocket/tsocket_bsd.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 61 insertions(+), 1 deletion(-)
>
>diff --git a/lib/tsocket/tsocket_bsd.c b/lib/tsocket/tsocket_bsd.c
>index 8203755..0756fb3 100644
>--- a/lib/tsocket/tsocket_bsd.c
>+++ b/lib/tsocket/tsocket_bsd.c
>@@ -132,6 +132,43 @@ static int tsocket_bsd_common_prepare_fd(int fd, bool high_fd)
> 	return -1;
> }
> 
>+#ifdef HAVE_LINUX_RTNETLINK_H
>+/**
>+ * Get the amount of pending bytes from a netlink socket
>+ *
>+ * For some reason netlink sockets don't support querying the amount of pending
>+ * data via ioctl with FIONREAD, which is what we use in tsocket_bsd_pending()
>+ * below.
>+ *
>+ * We know we are on Linux as we're using netlink, which means we have a working
>+ * MSG_TRUNC flag to recvmsg() as well, so we use that together with MSG_PEEK.
>+ **/
>+static ssize_t tsocket_bsd_netlink_pending(int fd)
>+{
>+	struct iovec iov;
>+	struct msghdr msg;
>+	char buf[1];
>+
>+	iov = (struct iovec) {
>+		.iov_base = buf,
>+		.iov_len = sizeof(buf)
>+	};
>+
>+	msg = (struct msghdr) {
>+		.msg_iov = &iov,
>+		.msg_iovlen = 1
>+	};
>+
>+	return recvmsg(fd, &msg, MSG_PEEK | MSG_TRUNC);
>+}
>+#else
>+static ssize_t tsocket_bsd_netlink_pending(int fd)
>+{
>+	errno = ENOSYS;
>+	return -1;
>+}
>+#endif
>+
> static ssize_t tsocket_bsd_pending(int fd)
> {
> 	int ret, error;
>@@ -640,6 +677,7 @@ struct tdgram_bsd {
> 	void *event_ptr;
> 	struct tevent_fd *fde;
> 	bool optimize_recvfrom;
>+	bool netlink;
> 
> 	void *readable_private;
> 	void (*readable_handler)(void *private_data);
>@@ -892,7 +930,12 @@ static void tdgram_bsd_recvfrom_handler(void *private_data)
> 	int err;
> 	bool retry;
> 
>-	ret = tsocket_bsd_pending(bsds->fd);
>+	if (bsds->netlink) {
>+		ret = tsocket_bsd_netlink_pending(bsds->fd);
>+	} else {
>+		ret = tsocket_bsd_pending(bsds->fd);
>+	}
>+
> 	if (state->first_try && ret == 0) {
> 		state->first_try = false;
> 		/* retry later */
>@@ -1395,6 +1438,11 @@ int _tdgram_bsd_existing_socket(TALLOC_CTX *mem_ctx,
> {
> 	struct tdgram_context *dgram;
> 	struct tdgram_bsd *bsds;
>+#ifdef HAVE_LINUX_RTNETLINK_H
>+	int result;
>+	struct sockaddr sa;
>+	socklen_t sa_len = sizeof(struct sockaddr);
>+#endif
> 
> 	dgram = tdgram_context_create(mem_ctx,
> 				      &tdgram_bsd_ops,
>@@ -1409,6 +1457,18 @@ int _tdgram_bsd_existing_socket(TALLOC_CTX *mem_ctx,
> 	talloc_set_destructor(bsds, tdgram_bsd_destructor);
> 
> 	*_dgram = dgram;
>+
>+#ifdef HAVE_LINUX_RTNETLINK_H
>+	/*
>+	 * Try to determine the protocol family and remember if it's
>+	 * AF_NETLINK. We don't care if this fails.
>+	 */
>+	result = getsockname(fd, &sa, &sa_len);
>+	if (result == 0 && sa.sa_family == AF_NETLINK) {
>+		bsds->netlink = true;
>+	}
>+#endif
>+
> 	return 0;
> }
> 
>-- 
>2.5.0
>

Flags:

metze: review+
vl: review+
martins: review+

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Attachments on bug 11714: 11839